Positioning device

Abstract

A positioning device includes a swiveling shaft, at one end of which an element to be positioned may be attached, a swivel drive, made up of a rotor, which is movable relative to a stator, a position measuring device, made up of two parts movable relative to each other, and a roller bearing, which includes several rolling elements. The rotor of the swivel drive and a first part of the position measuring device are connected to the shaft in a rotatably fixed manner. The rolling elements are made of a ceramic material.

1. A positioning device, comprising:
 a swivel shaft including one end configured to attach to an element to be positioned; 
 a swivel drive including a rotor movable relative to a stator; 
 a position measurement device including two parts movable relative to each other; and 
 a roller bearing including a plurality rolling elements, at least a partial number of the rolling elements made of a ceramic material; 
 wherein the rotor of the swivel drive and a first part of the position measurement device are connected, fixed against relative rotation, with the shaft; and 
 wherein arranged along the shaft, starting from the one end of the shaft, are first the roller bearing, then one of: (a) the first part of the position measuring device; and (b) the rotor. 
 
   
   
     2. The positioning device according to  claim 1 , wherein mass centers of the rolling elements are arranged along a circular line, and a ratio of a length of a circumference of the circular line to the number of the rolling elements, which are arranged along the circular line, is smaller than 5 mm. 
   
   
     3. The positioning device according to  claim 1 , wherein mass centers of the rolling elements are arranged along a circular line, and a ratio of a length of a circumference of the circular line to the number of the rolling elements, which are arranged along the circular line, is smaller than 3 mm. 
   
   
     4. The positioning device according to  claim 1 , wherein the swivel drive includes an electrical direct drive. 
   
   
     5. The positioning device according to  claim 1 , wherein the swivel drive includes a synchronous direct drive. 
   
   
     6. The positioning device according to  claim 1 , wherein the swivel shaft is swivelable by the swivel drive in a swivel range of less than ±180°. 
   
   
     7. The positioning device according to  claim 1 , wherein the swivel shaft is swivelable by the swivel drive in a swivel range of less than ±90°. 
   
   
     8. The positioning device according to  claim 1 , wherein the roller bearing includes two bearing rings made of a metallic material, the rolling elements arranged between the bearing rings. 
   
   
     9. The positioning device according to  claim 1 , wherein the bearing elements are made of Si 3 N 4 . 
   
   
     10. The positioning device according to  claim 1 , wherein the position measurement device is configured to perform photoelectric scanning. 
   
   
     11. The positioning device according to  claim 1 , wherein the position measurement device is configured to perform photoelectric scanning according to an interferential measurement principle. 
   
   
     12. The positioning device according to  claim 10 , wherein the first part of the position measurement device and a second part of the position measurement device include at least one of (a) transparent phase grating and (b) a reflection phase grating. 
   
   
     13. A positioning device, comprising:
 a swivel shaft including one end configured to attach to an element to be positioned; 
 a swivel drive including a rotor movable relative to a stator; 
 a position measurement device including two parts movable relative to each other; and 
 a roller bearing including a plurality rolling elements, at least a partial number of the rolling elements made of a ceramic material; 
 wherein the rotor of the swivel drive and a first part of the position measuring device are connected, fixed against relative rotation, with the shaft; and 
 wherein mass centers of the rolling elements are arranged along a circular line, a ratio of a length of a circumference of the circular line to the number of the rolling elements, which are arranged along the circular line, is smaller than 5 mm. 
 
   
   
     14. The positioning device according to  claim 13 , the ratio of the length of the circumference of the circular line to the number of the rolling elements, which are arranged along the circular line, is smaller than 3 mm. 
   
   
     15. The positioning device according to  claim 13 , wherein the swivel drive includes an electrical direct drive. 
   
   
     16. The positioning device according to  claim 13 , wherein the swivel drive includes a synchronous direct drive. 
   
   
     17. The positioning device according to  claim 13 , wherein the swivel shaft is swivelable by the swivel drive in a swivel range of less than ±180°. 
   
   
     18. The positioning device according to  claim 13 , wherein the swivel shaft is swivelable by the swivel drive in a swivel range of less than ±90°. 
   
   
     19. The positioning device according to  claim 13 , wherein the roller bearing includes two bearing rings made of a metallic material, the rolling elements arranged between the bearing rings. 
   
   
     20. The positioning device according to  claim 13 , wherein the bearing elements are made of Si 3 N 4 . 
   
   
     21. The positioning device according to  claim 13 , wherein the position measurement device is configured to perform photoelectric scanning. 
   
   
     22. The positioning device according to  claim 13 , wherein the position measurement device is configured to perform photoelectric scanning according to an interferential measurement principle. 
   
   
     23. The positioning device according to  claim 21 , wherein the first part of the position measurement device and a second part of the position measurement device include at least one of (a) transparent phase grating and (b) a reflection phase grating.